ABSTRACT Globally and in sub-Saharan Africa, adolescent females are at highest risk for HIV. In this region, there are also high levels of gender-based violence and a cultural preference for dry sex. Young women in Southern Africa become sexually active at around 15 years of age similar to those in the US9 and UK10. Adolescence is associated with significant changes in hormone levels, resulting in changes in cervical anatomy that could put them at risk for HIV. Vaginal insertion practices (VIPs) are common in women in sub-Saharan Africa. These VIPs [including intravaginal use of cloth or paper, insertion of products to dry/tighten the vagina and intravaginal cleansing with soap were associated with increased risk for HIV infection5. In four different studies conducted in South Africa, VIP prevalence ranged from 17.9% to 90.1%, depending on the population studied, with the predominant practices being intravaginal washing with soap, cloth or tissue paper for cleansing5. Relationship power inequity and intimate partner violence increase risk of incident HIV infection in young South African women20 This study will evaluate the hypothesis that in adolescent women, sexual immaturity, use of vaginal products and gender-based violence increase genital inflammation, damage the mucosa, alter the vaginal flora, which influences genital HIV target cell availability. To address this hypothesis, we propose two specific aims using two cohorts of HIV-negative SA adolescents in regions differentially at risk for HIV infection and with differing cultural norms for vaginal product use. We propose to enroll 300 adolescent females (aged 14-19 years) and 100 adult women (aged 25-35) and cluster them according to VIP use: (1) nothing (control); (2) using cloth or paper to wipe out the vagina; (3) intravaginal cleansing with soap; (4) intravaginal cleaning with household cleaners; or (5) products to dry/tighten vagina. Information about exposure to gender-based violence will be collected through the questionnaire. At baseline, examination of the cervix; vaginal vaginal flora, and imunity will be assessed. All women will be followed longitudinally for two consecutive sexual exposures. Women will be evaluated at baseline, <48 hours following sex (trauma visit), and at 7 days (wound healing). Comparing each subject to their own baseline, to the control arm, and to adult women, and building on adolescent trial experience at both clinical sites involved are strengths of this study design. The specific aims of this proposal are: 1. To examine anatomical and immunological characteristics of the adolescent state that may contribute to higher inflammation in the reproductive tract, hence HIV risk 2. To compare inflammatory responses to VIPs and sexual violence in adolescent females and older women The study outlined here may uncover why African adolescents are so disproportionately affected by HIV and has the potential to dramatically influence public health messaging about VIPs and sexual violence to adolescents in developing countries.